DEFENCE

Animals have evolved many ways of protecting themselves
from PREDATORS. Most use their keen senses to detect an attack and
make a dash for safety. Some animals are able to camouflage themselves. Others
have sharp spines, produce poisons, or make themselves look bigger than they
actually are. A few animals lose limbs or tails deliberately as a means of
escape, only to regenerate them later. Nevertheless, predators have also
evolved – and are better at catching prey.

Some amphibians defend themselves by producing poisons. Predators of
poison- dart frogs, such as snakes and spiders, are not harmed by mild poisons.
So these frogs have evolved highly poisonous skin secretions that are
unpleasant or even lethal to their predators. These frogs have also developed
colourful markings to warn predators that they are dangerous.

Several animals, including porcupines and sea urchins, have spines
for defence. The spiny puffer fish has spines but also another form of defence.
When attacked, it inflates its body by swallowing large amounts of water. As
its body swells, the spines stand up. The swollen fish sticks in the throat of
any attacker and cannot be swallowed.

Snakes have two methods for killing large prey. Venomous snakes
bite their quarry, injecting venom that affects the quarry’s nervous or
circulatory systems. Constricting snakes grab their prey and suffocate it by
throwing coils of their body around it. They strike with great speed but may
take several hours to eat a large animal.

MIMIC BUTTERFLY

Many butterflies have markings known as false eyes on their wings.
Those of the owl butterfly mimic the eyes of an owl and so frighten off small
birds that might normally be eaten by owls.

CAMOUFLAGE

Many flatfish that rest on the sea floor, such as plaice, are able
to change the colour of their skin to match the ground they are lying on. This
makes them almost invisible to predators. Just under the surface of their skin,
there are special cells that can become lighter or darker. Other animals that
can change colour to match their surroundings include chameleons and squid.

TREE SKINK TRICK

Some lizards, such as the skink, can shed part of their tail if they
are attacked from behind. The tail continues to move in the attacker’s
mouth, drawing attention away from the escaping skink. The skink is then able
to grow another tail.

PREDATORS

Animals that kill other animals for food are called
predators. Predation is the main reason why a creature of one species attacks a
member of another species. Animals being attacked may defend their young or
family group, but in most cases they try and escape capture. Some creatures eat
members of their own species – usually the eggs or younger members.
Predators may actively hunt for food or lie in wait to catch it.

PACK ATTACK

African hunting dogs take it in turns to head the chase so they
can wear out the prey before they wear out themselves. When the prey eventually
tires, they all move in together for the kill. Several types of mammal
predators hunt in groups. This allows them to tackle prey that would be too
big, dangerous, or tiring for them to tackle alone.